A travel eSIM works on a cruise only while the ship is in port or close enough to shore to reach land masts; at sea, your phone either connects to the ship's own satellite-linked cellular network, at roaming prices, or to the ship's Wi-Fi. On an Antarctic expedition, there's no mobile network to roam onto at all once you leave the South American coast. What works is the ship's satellite internet, which on many expedition ships is now Starlink and often included in the fare, and a satellite messenger on the Iridium network if you want your own emergency link.
We haven't sailed to Antarctica for this site. Everything below comes from the carriers', cruise lines' and travel writers' pages linked in each section, with their dates.
On a cruise ship: three ways to get online
| Option | Where it works | What it costs | Source |
|---|---|---|---|
| Travel eSIM | In port and near the coast; drops once the ship reaches open sea | Your normal eSIM price for that country | Cruise Critic, updated 22 Dec 2025 |
| Ship's cellular network ("Cellular at Sea", "901") | At sea, in international waters, on participating ships | AT&T: $20 per line per day; Verizon: $20 a day | AT&T, Android Authority |
| Ship Wi-Fi | Anywhere on board | Set by the cruise line; often a daily or voyage package | Your cruise line |
The detail behind the carrier prices:
- AT&T International Day Pass at sea: $20 per line per 24 hours, on "over 400 cruise ships". On certain ships, "after 500MB of data use within a 24-hour period, data speeds may be reduced to a maximum of 512Kbps." AT&T's page states a 10-day cap on daily fees for land and air travel but no cap for cruise days. (Page updated 2 March 2026.)
- Verizon Cruise Daily Pass: $20 a day with 500 MB of high-speed data, then 3G speeds, on over 200 ships across more than 25 cruise lines, per Android Authority (April 2025).
- T-Mobile: Cruise Critic's guide (updated December 2025) says some carriers, "such as T-Mobile", don't yet offer data on cruise ships. Check before you sail.
The trap is the automatic connection. Cruise Critic says the ship's network becomes available "once your ship reaches international waters", and your phone may join it without asking. If you don't want to pay $20 a day, turn off data roaming on your home line (or use airplane mode with Wi-Fi on) as the ship leaves port, and switch your travel eSIM back on as you dock.
Our take: for a cruise with several port days, a regional eSIM covering the ports plus the ship's Wi-Fi package at sea is usually the cheaper mix. A carrier's $20 day pass makes sense for a sea day when you must make calls on your own number.
In Antarctica
There's no mobile network for visitors. Wikipedia's telecommunications in Antarctica article mentions mobile phone servers only at Argentina's Marambio research base, for its own use. We found no carrier cruise pass that names an Antarctic expedition ship. What you'll actually use:
Ship Wi-Fi. Expedition ships have moved quickly to satellite internet in the last few seasons:
| Operator | Wi-Fi on Antarctic voyages | Source |
|---|---|---|
| Quark Expeditions | Free for every guest, one device at a time, "for basic Internet browsing, texting, emails, posting on social media and voice applications"; premium packages for heavier use. From the 2024/25 season | Quark, Nov 2023 |
| Ponant | Free Wi-Fi included in the fare | Unsold Antarctica |
| Lindblad / National Geographic | Basic Starlink complimentary (not on Delfin II); Enhanced and Premium tiers paid | Unsold Antarctica |
| Aurora Expeditions, Swan Hellenic | Complimentary for all guests | Unsold Antarctica |
| Scenic | "Complimentary, unlimited Wi-Fi for all guests" | Unsold Antarctica |
| Atlas Ocean Voyages | 1 GB complimentary; the author paid $100 for 2 GB more | Unsold Antarctica |
"Unsold Antarctica" is What to Expect with Internet Connectivity in Antarctica for the 2024-2025 Season, by Emily Johnson, Unsold Antarctica's operations manager, who sailed to Antarctica in 2024. Policies change between seasons; confirm with your operator.
The same round-up says some operators (it names Quark, Oceanwide, Albatros, Antarctica21, G Adventures, Polar Latitudes and Intrepid) used geostationary or unspecified satellite providers at the time, which it describes as having "varying speeds, limited data allowances and high latency" compared with Starlink. If your operator is one of those, ask what's included before you plan to upload photos at sea.
Your own emergency link. Apple's Emergency SOS via satellite works in 21 listed countries (5 October 2026), and Antarctica isn't one of them. Garmin inReach devices and ZOLEO use the Iridium network, which covers the whole planet including the poles. On a ship-based trip with landings led by expedition staff, you don't strictly need one; on a private voyage, a fly-in trip or a long kayak or camping add-on, we'd carry one. inReach vs ZOLEO vs SPOT compares the cost.
Before and after: the port cities
If your voyage starts in Ushuaia (Argentina) or Punta Arenas (Chile), you'll want data for a few days either side of it. Our Patagonia guide covers one eSIM for both countries; for Argentina alone, two weeks at 0.5 GB a day:
eSIM prices · Argentina
14 days at 0.5 GB a day (7 GB)
| Provider and cheapest fit | Price |
|---|---|
| Ubigi10 GB · 30 daysNetwork not named | $23 |
| Maya MobileUnlimited · 14 daysNetwork not named | $27.99 |
| Nomad10 GB · 30 daysNetwork: Movistar | $28 |
| Saily3 × 3 GB · 30 daysNetwork not named | $29.97 |
| Lotso TravelOurs10 GB · 15 daysNetwork not named | $30.99 |
| HolaflyUnlimited · 15 daysNetwork: Telefónica (Movistar) | $51.50 |
| Airalo2 × Unlimited · 7 days, 3 GB/day full speedNetwork: Movistar | $69 |
Public USD prices checked 31 Oct 2026. Lotso Travel is run by the team behind this site. Full data and method: price index; change the trip length in the calculator.
Ubigi and Maya Mobile were cheapest for Argentina in our data, with Nomad, which names Movistar as its network, close behind. Lotso Travel, which our team runs, sells an Argentina plan too, at a few dollars more; it doesn't name its Argentine network. Buy a plan valid for 30 days if your voyage is long, so the return leg is covered on the same eSIM.
- Data roaming switched off on your home line before the ship leaves port
- A travel eSIM for the port countries, valid long enough to cover the return
- Your operator's Wi-Fi terms in writing, especially on non-Starlink ships
- Low Data Mode (iPhone) or Data Saver (Android) on, to stretch a ship data allowance
- An Iridium messenger for private voyages or camping ashore
Questions people ask
Does a travel eSIM work on a cruise ship?
Only in port or close enough to shore to reach land masts. Once the ship is in open water, your phone can only connect to the ship's own maritime network (often shown as "Cellular at Sea" or "901"), which travel eSIMs don't cover. Use ship Wi-Fi at sea and the eSIM in port.
How much does phone service cost on a cruise ship?
AT&T charges $20 per line per day at sea through its International Day Pass, on over 400 ships, with speeds that may drop to 512 kbps after 500 MB. Verizon's Cruise Daily Pass is also $20 a day with 500 MB of high-speed data, on over 200 ships. Check your carrier's ship list first.
Is there phone signal in Antarctica?
Not for visitors. Antarctica has no public mobile network that a tourist's phone can use; a few research bases run their own systems. Expedition ships rely on satellite internet, and on many ships that's now Starlink.
Does iPhone satellite SOS work in Antarctica?
Don't rely on it. Apple's Emergency SOS via satellite works in 21 listed countries, and Antarctica isn't one of them. A Garmin inReach or ZOLEO, which use the Iridium network, cover the whole planet including the poles.
Do Antarctic expedition ships have Wi-Fi?
Most do now. Quark Expeditions has offered free Wi-Fi for one device per guest since the 2024/25 season, and a 2024/25 round-up by Unsold Antarctica lists Starlink or free Wi-Fi on Ponant, Silversea, Lindblad (basic tier), Aurora, Scenic and Viking, while some smaller operators still sell data by the package.